Orbital metastasis secondary to pulmonary adenocarcinoma treated with gefitinib: a case report.

INTRODUCTION: Orbital metastases of lung cancer are rare. However, because the number of patients diagnosed with lung cancer is increasing, the probability that a physician will see a patient with an orbital metastasis is also increasing. Unfortunately, the clinical course and response of these patients to cytotoxic chemotherapy are generally poor and keeping a patient's quality of vision is difficult. In recent years, gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, has brightened the outlook for patients with advanced non-small cell lung cancer, especially for those who carry epidermal growth factor receptor-activating mutations.

CASE PRESENTATION: A 62-year-old Japanese man presented with swelling of the eyelid margin and ptosis of his right eye. A physical examination revealed double vision in his right eye and an alteration in elevator muscle mobility. A magnetic resonance image demonstrated a right intra-orbital mass (18 × 16mm). Screening examinations were carried out because this mass was suspected to be a metastasis from another organ. Chest computed tomography revealed a 42 × 37mm mass shadow on the left side of the hilum with mediastinal lymph node metastases. Adenocarcinoma with an epidermal growth factor receptor gene mutation (exon 19 deletion L747-E749; A750P) was detected in a transbronchial biopsy specimen; the patient was diagnosed with stage IV (T2N2M1) non-small cell lung cancer.Gefitinib (250mg/day) was chosen as first-line chemotherapy because there was no pre-existing interstitial shadow. After two months of treatment, the patient's right eye opened completely and follow-up magnetic resonance imaging revealed a marked reduction of the intra-orbital mass to 14 × 13mm. Three months after treatment initiation, a follow-up computed tomography showed a marked reduction in the size of the primary lesion to 23 × 20mm. The patient is continuing gefitinib treatment without any adverse effects noted on computed tomography, physical, or laboratory examination.

CONCLUSIONS: We report the case of a patient with an orbital non-small cell lung cancer metastasis with epidermal growth factor receptor-activating mutations. This metastasis, as well as the primary lesion, showed a marked response to the molecular targeting drug gefitinib, and the patient's vision was kept without an invasive procedure. Gefitinib may be a good first choice for patients with orbital non-small cell lung cancer metastasis harboring epidermal growth factor receptor-activating mutations.